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Increasing Trends Towards Drinking Water Reclamation from Treated Wastewater
Issue:
Volume 3, Issue 1, March 2018
Pages:
1-9
Received:
10 November 2017
Accepted:
17 November 2017
Published:
5 December 2017
Abstract: All around the world, water supplies are coming under increasing pressure as population growth, climate change, pollution, and changes in land use affect water quantity and quality. To address existing and anticipated water shortages, many communities are working to increase water conservation and are seeking alternative sources of water. Water reuse—the use of treated wastewater, or “reclaimed” water, for beneficial purposes such as drinking, irrigation, or industrial uses—is one option that has helped some communities significantly expand their water supplies. This review summarizes the main findings of the literature. The paper provides an overview of the options and outlook for water reuse in the world, discusses water treatment technologies and potential uses of reclaimed water, and presents a new analysis that compares the risks of drinking reclaimed water to those of drinking water from traditional sources. Involved technologies in wastewater treatment plant for drinking water purpose should be furnished with highly performant methods such as membrane processes (nanofiltration, reverse osmosis) and advanced oxidation processes (H2O2, O3, etc.). Treating efficiently wastewater at its source is the best “barrage” against pollutants diffusion through the nature as chemicals of emerging concern are detected in tap water.
Abstract: All around the world, water supplies are coming under increasing pressure as population growth, climate change, pollution, and changes in land use affect water quantity and quality. To address existing and anticipated water shortages, many communities are working to increase water conservation and are seeking alternative sources of water. Water reu...
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Dealing with Outlier in Linear Calibration Curves: A Case Study of Graphite Furnace Atomic Absorption Spectrometry
Njaka Namelantsoa Andriamahenina,
Elise Octavie Rasoazanany,
Herinirina Nomenjanahary Ravoson,
Lucienne Voahangilalao Rakotozafy,
Manovantsoatsiferana Harinoely,
Raoelina Andraimbololona,
Randrianarivony Edmond
Issue:
Volume 3, Issue 1, March 2018
Pages:
10-16
Received:
16 November 2017
Accepted:
24 November 2017
Published:
2 January 2018
Abstract: Outlier in the calibration of lead by graphite furnace atomic absorption spectrometry (GF-AAS) has been studied with help of the statistical tool F-test and T-test. The process consisted on measuring five standard solutions with three replicate to prepare the calibration curve. Ordinary least squares method (OLSM) was used to get the equation of the linear calibration curve; the correlation coefficient R² and analysis of variance (ANOVA) was used to validate the linearity of this calibration curve. Proceeding to the graphic representation and the residual plot of the calibration, a suspected outlier was found. The statistical tool F-test and T-test were used to examine the suspected outlier, they yield the same result and confirm the outlier data. The calibration curve with and without the outlier data were taken care to investigate the effect of this outlier in the limit of detection (LOD), limit of quantification (LOQ), the concentration of lead in the fourteen samples and the uncertainty related to calibration curve. It has been observed that the linearity of the calibration curve is accepted for both cases. For the case of the calibration with the outlier, the estimated LOD and LOQ were 1.76 µg L-1 and 5.18 µg L-1, respectively. The concentrations of lead in the sample are between 2.85 µg L-1 and 22.61µg L-1 and the uncertainty related to calibration curve vary between 1.17µg L-1 and 1.41 µg L-1. On the other hand, for the calibration without the outlier data, the value of LOD and LOQ were improved compared to the previous value, the value of these two parameters were 1.32 µg L-1 and 3.96 µg L-1, respectively. The concentration of lead in the sample vary between 2.75 µg L-1 and 22.52 µg L-1, compared to the previous concentration these value decrease from 0.40% and 3.29%. The uncertainties related to calibration curve vary between 0.90 µg L-1 and 1.09 µg L-1 for the second case, compared to the uncertainty in the first case, the uncertainty decreases from 22.48% to 23.53%. In conclusion, dealing with outlier improves the quality of the measurement and allow producing a reliable analytical data.
Abstract: Outlier in the calibration of lead by graphite furnace atomic absorption spectrometry (GF-AAS) has been studied with help of the statistical tool F-test and T-test. The process consisted on measuring five standard solutions with three replicate to prepare the calibration curve. Ordinary least squares method (OLSM) was used to get the equation of th...
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Studying The Influence of Various Geometrical Parameters of Single-Walled Carbon Nano-Tubes of Armchair Chirality Type on Its Mechanical Behavior
Issue:
Volume 3, Issue 1, March 2018
Pages:
17-27
Received:
21 October 2017
Accepted:
21 November 2017
Published:
10 January 2018
Abstract: In the present work, the profound information on the mechanical properties of carbon nano-tubes (CNTs) were presented as an application of nano-technology in nano-materials are being most powerful in the current world. This would focuses/emphasis for designing and optimizing the CNTs based materials. Computational modeling technique was applied and developed to examine the mechanical characteristics for single-walled carbon nano-tube (SWCNT) of armchair chirality type. The atomistic based finite element method (FEM) was used to investigate the influence of various geometrical properties (diameter, wall thickness, and height-to-diameter ratio) of SWCNT armchair of chirality type on Poisson’s ratio and Young’s modulus values. Atomistic based finite element modeling was successfully developed and explored the mechanical behaviour of SWCNT exactly. The results were shown that the investigated geometrical parameters had much influenced on the mechanical properties of SWCNTs.
Abstract: In the present work, the profound information on the mechanical properties of carbon nano-tubes (CNTs) were presented as an application of nano-technology in nano-materials are being most powerful in the current world. This would focuses/emphasis for designing and optimizing the CNTs based materials. Computational modeling technique was applied and...
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Fluoride Determination in Pickling Solution of Stainless Steel by Ion Selective Electrode
Yusuf Yildiz,
Angela Jan,
Sapan Patel
Issue:
Volume 3, Issue 1, March 2018
Pages:
28-31
Received:
23 February 2018
Accepted:
11 March 2018
Published:
9 April 2018
Abstract: The Fluoride Ion Selective Electrode is an ion-selective sensor and will quickly and accurately measure fluoride ion activity rather than concentration in aqueous solutions. Fluoride ion activity depends on the solution total ionic strength and pH, and on fluoride complexing species. Adding an appropriate buffer provides a nearly uniform ionic strength background, adjust pH, and breaks up complexes so that, in effect, the electrode measures concentration. Pickling removes a thin surface layer from the stainless, using an acid solution, which is usually a hydrofluoric acid (HF) and nitric acid (HNO3), also called mixed acid. In this study, fluoride ion strength has been measured of pickling waste water from stainless steel by ion selective electrode. The results met the specification.
Abstract: The Fluoride Ion Selective Electrode is an ion-selective sensor and will quickly and accurately measure fluoride ion activity rather than concentration in aqueous solutions. Fluoride ion activity depends on the solution total ionic strength and pH, and on fluoride complexing species. Adding an appropriate buffer provides a nearly uniform ionic stre...
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